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1.
Summary A simple method for making detailed measurements of seedling root systems is described. Photocopies of root systems are traced
over by an operator using a digitizing system attached to a microcomputer. The computer calculates and prints the lengths
of axis, laterals and sublaterals for each root system. Accurate measurements can be achieved with a degree of speed and detail
unobtainable by other methods. 相似文献
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摘要 目的:胃复春片联合兰索拉唑肠溶片对慢性萎缩性胃炎(CAG)患者血清胃肠激素、炎症因子及免疫功能的影响。方法:选取62例CAG患者,根据门诊挂号奇偶性分为对照组(n=31,兰索拉唑肠溶片治疗)和研究组(n=31,胃复春片联合兰索拉唑肠溶片治疗)。比较两组患者疗效、胃肠激素[胃泌素(GAS)、胃动素(MTL)]、炎症因子[超敏C反应蛋白(hs-CRP)、肿瘤坏死因子-α(TNF-α)、白介素-6(IL-6)]、免疫功能及不良反应。结果:研究组治疗2个月后的总有效率为87.10%(27/31),高于对照组的64.52%(20/31),差异有统计学意义(P<0.05)。治疗2个月后,研究组hs-CRP、TNF-α、IL-6、GAS、CD8P低于对照组,MTL、CD4P、CD4+/CD8+高于对照组(P<0.05)。两组不良反应发生率对比未见明显差异(P>0.05)。结论:胃复春片联合兰索拉唑肠溶片治疗CAG疗效确切,可有效改善机体胃肠激素、炎症因子水平及免疫功能,且安全可靠,具有一定应用价值。 相似文献
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Mamdouh M. Ghorab Heba M. Abdel-Salam Marwa A. El-Sayad Mohammed M. Mekhel 《AAPS PharmSciTech》2004,5(4):63-68
The purpose of this research was to evaluate β-cyclodextrin (β-CD) as a vehicle, either singly or in blends with lactose (spray-dried
or monohydrate), for preparing a meloxicam tablet. Aqueous solubility of meloxicam in presence of β-CD was investigated. The
tablets were prepared by direct compression and wet granulation techniques. The powder blends and the granules were evaluated
for angle of repose, bulk density, compressibility index, total porosity, and drug content. The tablets were subjected to
thickness, diameter, weight variation test, drug content, hardness, friability, disintegration time, and in vitro dissolution
studies. The effect of β-CD on the bioavailability of meloxicam was also investigated in human volunteers using a balanced
2-way crossover study. Phase-solubility studies indicated an AL-type diagram with inclusion complex of 1∶1 molar ratio. The powder blends and granules of all formulations showed satisfactory
flow properties, compressibility, and drug content. All tablet formations prepared by direct compression or wet granulation
showed acceptable mechanical properties. The dissolution rate of meloxicam was significantly enhanced by inclusion of β-CD
in the formulations up to 30%. The mean pharmacokinetic parameters (Cmax, Ke, and area under the curve [AUC]0−∞) were significantly increased in presence of β-CD. These results suggest that β-CD would facilitate the preparation of meloxicam
tablets with acceptable mechanical properties using the direct compression technique as there is no important difference between
tablets prepared by direct compression and those prepared by wet granulation. Also, β-CD is particularly useful for improving
the oral bioavailablity of meloxicam. 相似文献
5.
Trace analysis of N‐acetyl‐L‐cysteine using luminol–H2O2 chemiluminescence system catalyzed by silver nanoparticles 下载免费PDF全文
N‐Acetyl‐L‐cysteine (NAC) can inhibit the luminol–H2O2, reaction, which is catalyzed by silver nanoparticles. Based on this phenomenon a new method was developed for NAC determination. Under optimum conditions, a linear relationship between chemiluminescence intensity and NAC concentration was found in the range 0.034–0.98 µg/mL. The detection limit was 0.010 µg/mL (S/N =3), and the relative standard deviation (RSD) was <5% for 0.480 µg/mL NAC (n =5). This simple, sensitive and inexpensive method has been applied to measure the concentration of NAC in pharmaceutical tablets. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
6.
Development and evaluation of acid-buffering bioadhesive vaginal tablet for mixed vaginal infections
An acid-buffering bioadhesive vaginal tablet was developed for the treatment of genitourinary tract infections. From the bioadhesion experiment and release studies it was found that polycarbophil and sodium carboxymethylcellulose is a good combination for an acid-buffering bioadhesive vaginal tablet. Sodium monocitrate was used as a buffering agent to provide acidic pH (4.4), which is an attribute of a healthy vagina. The effervescent mixture (citric acid and sodium bicarbonate) along with a superdisintegrant (Ac-Di-sol) was used to enhance the swellability of the bioadhesive tablet. The drugs clotrimazole (antifungal) and metronidazole (antiprotozoal as well as an antibacterial) were used in the formulation along with Lactobacillus acidophilus spores to treat mixed vaginal infections. From the ex vivo retention study it was found that the bioadhesive polymers hold the tablet for more than 24 hours inside the vaginal tube. The hardness of the acid-buffering bioadhesive vaginal tablet was optimized, at 4 to 5 kg hardness the swelling was found to be good and the cumulative release profile of the developed tablet was matched with a marketed conventional tablet (Infa-V). The in vitro spreadability of the swelled tablet was comparable to the marketed gel. In the in vitro antimicrobial study it was found that the acid-buffering bioadhesive tablet produces better antimicrobial action than marketed intravaginal drug delivery systems (Infa-V, Candid-V and Canesten 1). 相似文献
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Conclusion The summary is that the high humidity impaired the disintegrant property of α-cellulose in all 3 tablets tested. Tablets of
aspirin, which is the more hygroscopic drug, were also more sensitive to the humidity effect, while tablets of chloroquine
phosphate, which is a water-soluble drug, were the least sensitive to the humidity effect. The results permit the conclusion
that moisture uptake with subsequent gelling of the α-cellulose is the mechanism of impairment of its disintegrant property.
The tablets would not normally be stored under an RH as high as 100%, nevertheless, the results of the accelerated stability
study have underscored the need to protect tablets containing α-cellulose as disintegrant from moisture.
Published: August 10, 2005 相似文献
8.
This is the third of a series of articles detailing the development of near-infrared spectroscopy methods for solid dosage
form analysis. Experiments were conducted at the Duquesne University Center for Pharmaceutical Technology to develop a system
for continuous calibration monitoring and formulate an appropriate strategy for calibration transfer. Indcators of high-flux
noise (noise factor level) and wave-length uncertainty were developed. These measurements, in combination with Hotelling’s
T2 and Q residual, are used to continuously monitor instrument performance and model relevance. Four calibration transfer techniques
were compared. Three established techniques, finite impulse response filtering, generalized least squares weighting, and piecewise
direct standardization were evaluated. A fourth technique, baseline subtraction, was the most effective for calibration transfer.
Using as few as 15 transfer samples, predictive capability of the analytical method was maintained across multiple instruments
and major instrument maintenance. 相似文献
9.
The purpose of the present study was to develop an optimized gastric floating drug delivery system (GFDDS) containing metoprolol
tartrate (MT) as a model drug by the optimization technique. A 23 factorial design was employed in formulating the GFDDS with total polymer content-to-drug ratio (X1), polymer-to-polymer ratio (X2), and different viscosity grades of hydroxypropyl methyl cellulose (HPMC) (X3) as independent variables. Four dependent variables were considered: percentage of MT release at 8 hours, T50%, diffusion coefficient, and floating time. The main effect and interaction terms were quantitatively evaluated using a mathematical
model. The results indicate that X1 and X2 significantly affected the floating time and release properties, but the effect of different viscosity grades of HPMC (K4M
and K10M) was nonsignificant. Regression analysis and numerical optimization were performed to identify the best formulation.
Fickian release transport was confirmed as the release mechanism from the optimized formulation. The predicted values agreed
well with the experimental values, and the results demonstrate the feasibility of the model in the development of GFDDS. 相似文献
10.
Tramadol hydrochloride (TH), has become the most prescribed opioid worldwide. However, its neurotoxicity and abuse potential are not well documented. In the present study, TH administration induced abnormal behavior and body and brain mean weight loss. Two principal metabolites O- and N-desmethyltramadol were detected in the brain tissue, and N-desmethyltramadol was the main metabolite produced. A total of 30 differential protein spots were identified using semi-quantitative 2D-PAGE and proteomic analyses, and classified into 13 categories, in which subtypes of 14-3-3 proteins, creatine kinase, ATP synthase beta chain, and tubulin were identified at the separated location on the gels 3, 3, 4, and 11 times respectively. Many TH responsive proteins have functions related to oxidative stress, including 14-3-3 proteins, creatine kinase BB, ubiquitin carboxy-terminal hydrolase L-1, ATP synthase, synaptosome-associated protein, tubulin and actin. Irrespective of oxidative damage, other pathways affected include apoptosis, energy metabolism, signal disorders, and cytoskeletal structure. Ultrastructural observation of mitochondria showed a series of morphological changes in the case of TH exposure. 相似文献